Parties to the Black Sea grain pact are nearing a deal to extend it after talks between Ukrainian, Russian, Turkish and United Nations officials, Turkey’s Defence Minister Hulusi Akar said, writes Reuters.

Russia has threatened to quit the agreement on May 18 over obstacles to its grain and fertilizer exports and the four parties discussed U.N. proposals to extend the deal on Thursday.

“(The parties) are approaching an agreement on an extension of the grain agreement period”, - Akar said.

The Kremlin said early on Thursday that Russian President Vladimir Putin could speak with Turkish President Tayyip Erdogan at short notice if needed regarding an extension of the deal, but that there were no such plans yet.

Akar also said he had been told that an agreement was reached on the return to Turkey of six Turkish merchant vessels currently in Ukrainian ports.